By use of the procedures described above, 2D slices from 52 NBPs (13 for each of the 4 breast types) were extracted and virtually imaged to produced USCT measurement data. From these data, SOS images were reconstructed
on a grid with a pixel size of 0.2 mm by use of a previously published waveform inversion with source encoding (WISE) method[1]}. The reconstruction was initialized by use of a blurred version (Gaussian blur with 8 mm correlation length) of the true SOS.
Notably, the true values of the (constant) density
and AA coefficient were employed. Because these quantities were known and did not require estimation, the reconstructed SOS estimates are expected to generally be of higher quality than would be obtained if the density and attenuation properties had to be concurrently estimated with the SOS, or if incorrect fixed values of the density and attenuation properties were employed.
In this sense, it will be useful to compare these reconstructed SOS estimates
against the images reconstructed in the two case studies below.
